use kicad stepup extension.
You might want to read this topic, it has some heated opinions
Some people are uncomfortable with Y axis being flipped, some don’t care, for others it’s actually the right way down. Either way it will be configurable soon.
And yes, do use the stepup plugin for freecad, you won’t have to manually align your models or muck around with wrl settings. Makes exporting models (and few other operations) as easy as it can be.
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It will not happen in v5. And v6 is at least a year or two away. So i would not call it soon.
Patch for that is already in the middle of review, it will be in nightlies soon.
Even Freecad cannot reopen the exported model so i don’t know what happened.
Nightlies are not what i would count as “usable for production” (I know i know you are excited to tell everyone it will be available soon but please remember to add massive disclaimers about what nightlies are as most users are not used to such a concept.)
We even have a default disclaimer in the FAQ for this very reason: Is it a good idea to use a nightly build version?
Apparently lots of people never went to school 
This is not something i made up, every graph i have ever seey is done this way and when I joind a company that uses 3D CAD low and behold they do it the same as I was taught at school… Must be a conspiracy of some kind
2d Graphics programs (and some 2d graphics libraries) use top left as 0,0 and increase both axis from there. Meaning there is more than one convention (It even has a name. Left oriented coordinate system.)
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People who paid attention in school know that the direction of axis is completely arbitrary. Just because graphs are one way doesn’t mean CAD programs have to do the same. In computer graphics Y axis being downward is very common.
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Quite, if KiCad is to gain mainstream acceptance it must be stable unless you want to suffer the fate of circuit studio, i am sure i am not the first to leave a ship that is sure to sink and i will be mightily pissed off if a prgram I am trying to use to make serious products I wish to sell misbehaves and ruins designs. I will stick with current stable releases and be grateful.
you can flip your 2D space if you wish but you cannot do that with a 3D space as you flip the Z axis as well. Find me a graph or diagram that uses a flipped Y axis.
You think of it wrong. If you flip the z axis above the kicad coordinate system then it is a normal right handed one. (looked from below) It is however a left handed coordinate system which means the z axis still points out of the screen. (The mathematics behind it do not care.)
Here the german wiki article that explains this well: https://de.wikipedia.org/wiki/Rechtssystem_(Mathematik) - or see the https://en.wikipedia.org/wiki/Cartesian_coordinate_system (section In three dimensions for the english version)
The only real problematic thing i see with kicads coordinate system is that rotation (of for example pads) uses counter clockwise as positive which would mean a right hand coordinate system is used for that part. (arcs however use clockwise as positive angle which would be correct in kicads left handed system.)
Yes i said above that basically you are looking from the bottom, that is the only way of reconciling it. i don’t know about the math, i thought is was just an established convention the same as we all agree what is left and right. The yanks use a different 2D drawing projection from us but that is less of an issue because the relevance is only in the drawing itself and does not need to be compatible with other things.
I think the arrival of 3D models and the conversion of the space from 2D to 3D is causing the problem.
Nope. You still misunderstand. A left hand system is not a right hand system looked from below. There is no way to rotate one to the other. They are fundamentally different but equally valid. (They are mirror images of each other. Mirroring is an operation that we humans can not intuitively do for 3d things as it is something that is impossible for a real thing.)
And yes it is the case that a right hand system is kind of the norm nowadays. But not back when kicad was first developed. This is why an abstraction layer will be added in future to give users a way to view coordinates as they like them.
Yes i know. it often happens that 2 or more systems arise and only one wins which is what we all want or it becomes chaos. As i said above the only way to make the 2 systems work is to numerically flip all of one of the coordinate values in the 3D space in this case the Y axis or maybe the Z so that things line up again so the step model would have to be reprocessed. In most things we would not even notice as they are symetrical packages anyway.
The patch set currently being reviewed address only the layout editor “pcbnew”. The framework to handle axis direction control and origin translation in other apps is included but UI support will come later. I expect the footprint editor will be next.
Since these patches affect only how coordinates are presented to the user and not the internal representation, these patches don’t cause compatibility problems.
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You guys are probably all too young to know this.
Computer terminals used to start in the upper left corner and so did graphics when it came along.
Upper Left = (0,0) is the historical convention for many computers.
Numbers increased to the right and down.
I started programming when using 80-column punch cards was standard, then moved on to 80x24 character terminals (ADM3A and VT100). Graphical displays were something most people dreamed about using.
While the internal addressing of coordinates on a screen is interesting trivia, it’s utterly irrelevant to a CAD user. It makes no more sense than expecting the user of a word processing package to understand the internals of a disk drive.
Quite, screens are not CAD Humans read top to bottom but if i am in 3D space I tend to go up into the oir not down into the ground. Until we all walk around upsidedown Y+ will be up not down.
Hey, don’t blame us Yanks for this. I know we are pretty backwards with our absolute refusal (and failure at least once) to adopt the metric system. (Except for one stretch of interstate from Tuscon to Mexico where the highway is measured in km that was done as an experiment. There are enough locals that are fine with it, (and some even enjoy the novelty), there doesn’t seem to be any significant effort to normalize it to the rest of the interstate system measured in miles.) But KiCad’s origins are French. Blame the “Continentals” if you want, but this is one time that us Yanks aren’t to blame.
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